Which of the following below is a technique for stopping or preventing hackers from using buffer overflows to take control of a program.

Question $26$ options:

Randomizing the address where the program stack starts.

Using a $\text{'}$no$-$op sled'

Putting a special value, called a 'stack canary', after the buffer address that will detect if there is a buffer overflow.

Limiting where executable code can reside in memory.

Supporting variable sized stack frames.

Adding some padding to structs so that addresses are multiples of $8.$